- support negative start value (e.g. substr('hello',-2) returns 'lo')
- support negative length value (e.g. substr('hello',3,-1) returns 'll')
- length parameter now optional, defaults to end of string
(e.g. substr('hello world',7) returns 'world')
A new script then parses these json help files into the html help
contents, in a standardised manner. Previously, the function help
was a bunch of different formats and structures.
Now, a custom stylesheet can be applied (and later tweaked!) to
format these help. Eg, this commit colors variables and function
names in the syntax section for greater readability.
