Strings.toString doesn't compile with integer literals

[frangio]

As seen in the forum, Strings.toString(1) does not compile in 4.9.0 because 1 could be a signed or unsigned integer and toString is available for signed integers since #3773.

We should rename the function to toStringSigned so that the basic toString function can be used with integer literals.

[frangio]

@Amxx @ernestognw Would you agree with renaming this? If so we can mark this as good first issue.

[himansh295]

Hi @frangio is this issue is still open.I would like to work on it.