Changed a few things

- Bumped to 0.15.0
- Add boot script
- Change variable definition syntax, using a = to distinguish more cleary between identifier and value
- Variables initial values are evaluated on first use instead of at parsing time
- Error on variable redefinition. Means you should make sure to load saves after your scripts.
- Improve string parsing, support for escape codes
- Remove support for number literals with empty decimal part (42. for 42.0) as there's no distinction in Anselme and it conflicts with .function call suffix
- Changed priority of : pair operator
- Add type type, and type annotations to variables and function parameters
- Change Lua function system to use regular Anselme functions
  - Defining a function from Lua is now way simpler and require providing a full Anselme function signature
- Change Anselme function system
  - Dynamic dispatch, based on arity, type annotation and parameter names. Will select the most specific function at runtime.
  - Define way to overload most operators
  - Allow custom type to text formatters
  - Allow assignment to custom functions
  - Index operator ( renamed to ()
  - Functions with parameters each have their own private namespace (scoping ersatz)
  - Internal: "custom"-mode operators now have their own expression AST type instead of cluttering the function system
- Remove static type checker as it is barely useful with new function system. May or may not rewrite one in the future.
- Improve error messages here and there
- Internal: cleaning

test/tests/resume from nested paragraph.lua

@@ -17,24 +17,24 @@ _[49]={}
 _[48]={}
 _[47]={}
 _[46]={}
-_[45]={tags=_[63],data="c"}
-_[44]={tags=_[62],data="a"}
-_[43]={tags=_[61],data="Force p checkpoint:"}
-_[42]={tags=_[60],data="d"}
-_[41]={tags=_[59],data="c"}
-_[40]={tags=_[58],data="b"}
-_[39]={tags=_[57],data="From q checkpoint again:"}
-_[38]={tags=_[56],data="d"}
-_[37]={tags=_[55],data="c"}
-_[36]={tags=_[54],data="b"}
-_[35]={tags=_[53],data="From q checkpoint:"}
-_[34]={tags=_[52],data="d"}
-_[33]={tags=_[51],data="c"}
-_[32]={tags=_[50],data="a"}
-_[31]={tags=_[49],data="From p checkpoint:"}
-_[30]={tags=_[48],data="d"}
-_[29]={tags=_[47],data="x"}
-_[28]={tags=_[46],data="From start:"}
+_[45]={data="c",tags=_[63]}
+_[44]={data="a",tags=_[62]}
+_[43]={data="Force p checkpoint:",tags=_[61]}
+_[42]={data="d",tags=_[60]}
+_[41]={data="c",tags=_[59]}
+_[40]={data="b",tags=_[58]}
+_[39]={data="From q checkpoint again:",tags=_[57]}
+_[38]={data="d",tags=_[56]}
+_[37]={data="c",tags=_[55]}
+_[36]={data="b",tags=_[54]}
+_[35]={data="From q checkpoint:",tags=_[53]}
+_[34]={data="d",tags=_[52]}
+_[33]={data="c",tags=_[51]}
+_[32]={data="a",tags=_[50]}
+_[31]={data="From p checkpoint:",tags=_[49]}
+_[30]={data="d",tags=_[48]}
+_[29]={data="x",tags=_[47]}
+_[28]={data="From start:",tags=_[46]}
 _[27]={_[45]}
 _[26]={_[43],_[44]}
 _[25]={_[42]}