And:
- display them in stack traces
- expose them as Function.prototype.columnNumber
OP_line_num is renamed to OP_source_loc and the pc2line data structure
is extended with the column number in zigzag encoding.
The bytecode version number BC_VERSION is incremented because pc2line
data is read and written by JS_ReadObject() and JS_WriteObject() when
it is present.
Fixes: https://github.com/quickjs-ng/quickjs/issues/149
get_loc0 and get_loc1 are individually very frequent opcodes _and_ they
are very often paired together, making them ideal candidates for opcode
fusion.
Reduces microbench.js running time by about 4%.
