fix haplo rest url

README.md

@@ -122,7 +122,7 @@ The default output format is a simple tab-delimited file reporting all observed
 The altered haplotype sequences can be obtained by switching to JSON output using `--json` which will display them by default.
 Each transcript analysed is summarised as a JSON object written to one line of the output file.
 
-The JSON output structure matches the format of the [transcript haplotype REST endpoint](http://rest.ensembl.org/documentation/info/transcript_haplotypes_get).
+The JSON output structure matches the format of the [transcript haplotype REST endpoint](https://rest.ensembl.org/documentation/info/transcript_haplotypes_get).
 
 You may exclude fields in the JSON from being exported with `--dont_export field1,field2`. This may be used, for example, to exclude the full haplotype sequence and aligned sequences from the output with `--dont_export seq,aligned_sequences`.